In a spread spectrum receiver of a direct (DS) type using a convolver, information is demodulated from a correlation output which is obtained by applying a received input signal and a reference signal to the convolver.
In a conventional spread spectrum receiver, however, in which the level of a reference signal is constant, the peak value and the signal-to-noise (S/N) ratio of the correlation output vary with magnitude of the received input signal and deteriorates the efficiency of the receiver.